<template>
  <section class="msite">
    <!--首页头部-->
    <HeaderTop :title="address.name">
      <router-link slot="search" to="/search" class="header_search">
        <span class="iconfont icon-sousuo"></span>
      </router-link>
      <router-link slot="login" :to="userInfo._id ? '/userinfo': '/login'" class="header_login">
        <span class="header_login_text" v-if="!userInfo._id">登录 | 注册</span>
        <span class="header_login_text" v-else>
           <i class="iconfont icon-wode"></i>
        </span>
      </router-link>
    </HeaderTop>
    <!--首页导航-->
    <nav class="msite_nav">
      <div class="swiper-container" v-if="categorys.length">
        <div class="swiper-wrapper">
          <div class="swiper-slide" v-for="(foodType,index) in categorysArr" :key="index">
            <a href="javascript:" class="link_to_food" v-for="(food, index) in foodType" :key="index">
              <div class="food_container">
                <img :src="imgBaseUrl+food.image_url">
              </div>
              <span>{{food.title}}</span>
            </a>

          </div>

        </div>
        <!-- Add Pagination -->
        <div class="swiper-pagination"></div>
      </div>
      <img src="./images/msite_back.svg" alt="" v-else>
    </nav>
    <!--首页附近商家-->
    <div class="msite_shop_list">
      <div class="shop_header">
        <i class="iconfont icon-list"></i>
        <span class="shop_header_title">附近商家</span>
      </div>
      <ShopList></ShopList>
    </div>
  </section>
</template>

<script>
import BScroll from 'better-scroll'
import  Swiper  from 'swiper';
import 'swiper/swiper-bundle.min.css';
import HeaderTop from "../../components/HeaderTop/HeaderTop";
import ShopList from "../../components/ShopList/ShopList";
import {mapState} from "vuex";

export default {
  data () {
    return {
      imgBaseUrl: 'https://cube.elemecdn.com/'
    }
  },
  mounted () {
    this.$store.dispatch('getCategorys')
    this.$store.dispatch('getShops')
  },

  computed: {
    ...mapState(['address', 'categorys', 'userInfo']),

    /*
    根据categorys一维数组生成一个2维数组
    小数组中的元素个数最大是8
     */
    categorysArr () {
      const {categorys} = this
      // 准备空的2维数组
      const arr = []
      // 准备一个小数组(最大长度为8)
      let minArr = []
      // 遍历categorys
      categorys.forEach(c => {
        // 如果当前小数组已经满了, 创建一个新的
        if(minArr.length===8) {
          minArr = []
        }
        // 如果minArr是空的, 将小数组保存到大数组中
        if(minArr.length===0) {
          arr.push(minArr)
        }
        // 将当前分类保存到小数组中
        minArr.push(c)
      })

      return arr
    }
  },

  watch: {
    categorys (value) { // categorys数组中有数据了, 在异步更新界面之前执行

      // 界面更新就立即创建Swiper对象
      this.$nextTick(() => {// 一旦完成界面更新, 立即调用(数据更新之后)
        // 创建一个Swiper实例对象, 来实现轮播
        new Swiper('.swiper-container', {
          loop: true, // 可以循环轮播
          // 如果需要分页器
          pagination: {
            el: '.swiper-pagination',
          },
        })

        // new BScroll('.miste-content-wrapper', {
        //   click: true
        // })
      })

    }
  },

  components: {
    HeaderTop,
    ShopList
  }
}
</script>

<style lang="stylus" rel="stylesheet/stylus">
@import "../../common/stylus/mixins.styl"
&.msite  //首页
  width 100%
  overflow hidden
  .header_search
    position absolute
    left 15px
    top 50%
    transform translateY(-50%)
    width 10%
    height 50%
    .icon-sousuo
      font-size 20px
      color #fff

  .header_login
    font-size 14px
    color #fff
    position absolute
    right 15px
    top 50%
    transform translateY(-50%)
    .header_login_text
      color #fff
      .icon-wode
        font-size 20px
  .msite_nav
    bottom-border-1px(#e4e4e4)
    margin-top 45px
    height 200px
    background #fff
    .swiper-container
      width 100%
      height 100%
      .swiper-wrapper
        width 100%
        height 100%
        .swiper-slide
          display flex
          justify-content center
          align-items flex-start
          flex-wrap wrap
          .link_to_food
            width 25%
            .food_container
              display block
              width 100%
              text-align center
              padding-bottom 10px
              font-size 0
              img
                display inline-block
                width 50px
                height 50px
            span
              display block
              width 100%
              text-align center
              font-size 13px
              color #666
      .swiper-pagination
        >span.swiper-pagination-bullet-active
          background #0085ff
  .msite_shop_list
    top-border-1px(#e4e4e4)
    margin-top 10px
    background #fff
    .shop_header
      padding 10px 10px 0
      .shop_icon
        margin-left 5px
        color #999
      .shop_header_title
        color #999
        font-size 14px
        line-height 20px
</style>
